Train-control system



E. J. BLAKE. TRAIN CONTROL SYSTEM. APPLICATION FILED,DEC- 26. 1919.

Patented Jan. 24, 1922.

2 SHEETSSHEET I. 1 g. 1

INVENTOR ELI J. BLAKE. mfi-cwx xm ATTORNEY E. J. BLAKE.

TRAIN CONTROL SYSTEM.

APPLICATION FILED DEC-25,1919- Patented Jan. 24, 1922. 5 2 $HEETS-SHEET 2v INVENTUH EL] J. BLHKE A TTOR/VEY UNITED STATES.

PATENT OFFICE.

ELI J. BLAKE, OF BUFFALO, NEW YORK, ASSIGNOR TO HALL SWITCH & SIGNAL 00., A. CORPORATION OF MAINE.

TRAIN-CONTROL SYSTEM.

Specification of Letters Patent.

Patented Jan. 24, 1922.

Original application filed October 31, 1918, Serial No. 260,506. Divided and this application filed December 26, 1919.

To all whom it may concern:

Be it known that I, ELI J. BLAKE, a citizen of the United States, and a resident of Buffalo, county of Erie, State of New York, (whose post-ofiice address is Gould Coupler Company, Depew, New York,) have invented certain new and useful Improvements in Train-Control Systems, of which the following is a specification.

This is a division of my application Serial No. 260,506, filed October 31st, 1918.

The invention relates to means for automatically controlling the speed of moving vehicles.

One object is to provide a simple and reliable means to accomplish the above purpose.

Another object is to provide means whereby a multitude of different speed controls may be obtained.

A further object is to provide means for accomplishing the above purpose whereby failure of any essential part of the appara tus will arrest the progress of the vehicle.

Vith these and other objects in; view which will be apparent from the following I will now proceed to describe my invention.

Fig. 1 is a side elevation of one form of speed control apparatus.

Fig. 2 is a side elevation of a modified form of tripper.

Fig. 3 isa detail of means whereby different speed curves may be obtained.

Figure 1 of the attached sketches shows the principal features of the tripper opera-ted train control system. 1 is a mechanism case supported at one end by hearings on the axle 2 of a car or locomotive and at the other end by a spring supportB attached to a frame member 1.

5 is a gear keyed to the axle 2 and meshing with a loose wheel 6 on the shaft 10, on which is mounted a pawl 11 engaging a ratchet 12 which is keyed to the shaft 10.

T is a second gear keyed to the axle 2 and driving a loose wheel 9 on the shaft 10 through the intervening idle gear 8. The loose wheel 9 carries a pawl 18 which engages the ratchet 12, but revolves in a path which clears the pawl 11. It is evident that Serial No. 347,309.

the shaft 10 will revolve always in the left hand direction, irrespective of the direction of rotation of the axle 2.

14 and 15 are a pinion and gear preferably arranged to be conveniently replaced by another pair of slightly difierent ratio in order to adjust the angular travel of the shaft 16 to a definite proportion with the linear travel of the wheels when their diameter has been reduced by wear or turning.

17 is a pinion engaging a loose wheel 18 connected to the shaft 19 by a friction clutch 20.

21 is a pinion keyed to the shaft 19 and meshing with the sector gear 22. 23 is a cam member keyed to the shaft 24 and adapted when raised, to force the sector gear 22 to the position shown, and no farther though the stroke of the cam member may exceed the necessary stroke for forcing the sector gear to its extreme position.

25 is a crank keyed to the extension of the shaft 24 outside of the casing 1. It is lifted by tension spring 26 and pulled down by a link 27 connected to an extension of the shoe 28 which is pivoted at the side of the car.

29 is a tripper mounted beside the track on a shaft 30. It is normally raised into the path of the shoe 28 by a spring 31, and retained in that position by the latch 32. The latter is however adapted to be lifted out of engagement by the electromagnet 33. The springs 26 and 31 are so proportioned that when the latch 32 is disengaged the shoe 28 in passing over the tripper 29 will depress it without being displaced itself; but when the latch 32 is engaged, since the tripper cannot be depressed the shoe 28 is lifted, forcing the cam member 23 and the sector gear 22 to the position shown in the sketch.

The magnet 33 may be controlled by any suitable means to release the latch 32 at such times as it is proper to allow the car to pass the tripper 29 without actuating the stop mec'hanisnr. In the case illustrated it receives its energy from a battery; through the contact points of a. relay which in turn receives its energy from a battery 36 over the rails 37 and 38 of a block section in advance of the tripper 29. The

block section is shown short circuited by a pair of wheels 39, so that the relay 35 is open and the latch 32 engaged.

40 is a cam keyed to the shaft 19, shown at the extreme right hand limit of its travel, with the stop pin 42, which projects from the rear of the cam resting against a projection 41 on the back of the casing 1. At its opposite limit of motion the pin 42 would rest against the opposite side of the projection 41. 43 is a follower arm pivoted at 44 and carrying the insulated contact studs 45 and 46.

47 is a time arm attached to the sector gear 48 and carrying an insulated contact member 49. A spring 50 attached to the sector gear 48 tends to maintain contact between the members 49 and 45.

The sector gear acting through the pinion 51, the ratchet 52, the gears 53 and 54 and the pinions 55 and 56 drives a centrifugal governor 57 when the sector revolves in a right hand direction; but drives only the pinion 51 and the ratchet 52 when revolving in a left hand direction. Thus when the follower arm 43 is depressed the time arm 47 follows at a speed limited by the governor 57 ;Y but when the arm 43 is raised the arm 47 is free to be raised opposed only by the spring 50.

The time arm 58 carrying the contact member 59 is controlled by a train of wheels and a governor differing from those last described only in the fact that its governor is adjusted for a slightly higher speed limit in following downward movements of the arm 43.

Downward movements of the arms 47 and 58 are limited by stop pins 60 and 61 respectively at a point just short of the extreme travel of the follower arm 43.

The arm 43 at its lowest position rests against a latch 62. When the latch is lifted by the plunger magnet 63 it raises the arm 43 sufficiently to bring the studs 45 and 46 in contact with the members 49 and 59 when the latter are at their lower limits of motion.

The magnet 63 receives energy from the battery 64 through a centrifugal contact device 65 adjusted to close only when the train is practically at rest.

The contact stud 45 and the member 49 control the flow of current from the battery 64 to an indicating lamp 66 placed in View of the engineman. The contact stud 46 and the member 59 control the flow of current from the battery 64 through a magnet valve 67 connected to the air brake system in such a manner that interruption of curent in the magnet valve will result in the application of the brakes.

The parts that have been described operate in the following manner:

The tripper 29 is located in the rear of the entrance to the block which it protects by the maximum distance required for bringing a train to rest. .lVhen the block is unoccupied the relay 35 is closed and the latch 32 is raised so that the tripper 29 can be depressed. Under this condition the mechanism on the car is not afiected by its passage over the tripper. But if the block is occupied the relay 35 is open; the latch 32 is engaged and the shoe 28 is raised during its passage over the tripper forcing the cam 23 and the sector gear 22 to the position shown in Fig. 1. When the tripper has been passed the cam 23 is retracted by the spring 26 and the sector gear 22 is left free to follow the movements of the pinion 21, on the shaft 19. The gear 18, acting through the lfriction clutch 20 now drives the shaft 19 with the attached cam 40 in a left hand direction at a rate proportional to the speed of the-train so that the cam advances through a definite angle for each foot traversed by the train. .(The word train is here employed in a general sense to signify a car or locomotive or an assemblage of cars and locomotives). The position of the cam at any instant then corresponds to the distance traversed by the train after passing the tripper.

As the cam 40 revolves the lfollower arm 43 drops at a rate depending on the speed of the train and the obliquity of the cam at the point of contact with the follower. So long as the'speed does not exceed the limiting speed of the time arms 47 and 58 the contacts 45-49 and 46-59 remain closed. The lamp 66 remains lit and the magnet valve 67 is energized until the time arm sectors strike the stop pins 60 and 61. The lampis then extinguished, the magnet valve released and the brakes applied. But if the follower 43 drops at a speed exceeding the speed limit of the time arm 47 the contact 4549 will open and the lamp will be extinguished, warning the engineman that he is approaching the speed at which the brakes will be applied; and at a slightly higher speed the contact 46 59 will open releasing the magnet valve 67 and causing the brakes to be applied.

When the train has practically come to rest the centrifugal contact 65 closes causing the magnet 63 to raise the latch 62. If the follower arm 43 is at the lower limit of its stroke it will be raised slightly and retained by the latch 62 until it has been lifted again by the cam 40, allowing the latch 62 to drop to its normal position. The slight lifting of the arm 43 closes the contacts 4549 and 46-59, restoring current to the lamp 66 and the magnet valve 67. The train is now free to proceed. The cam 40 having reached the limit of its motion, with the stop pin 42 resting against the back of the projection 11, will remain stationary so that the friction clutch 20 is obliged to slip as the gear 18 revolves.

It is evident that the train speed, at any given distance beyond the tripper, which will cause an automatic application of the brakes can be determined by giving the cam aO a suitable obliquity at the corresponding point of its circumference. For example the speed at each point may be the highest speed that will permit of bringing the train to rest at the entrance to the occupied block, in which case the automatic application will occur only when it would otherwise be impossible to stop the train without entering the occupied block. If it is desired to enforce a constant speed limit, irrespective of distance, the cam 40 can be given a corresponding form.

The more usual requirement is that the train be brought to rest near the entrance to the occupied block, irrespective of the speed at which it is moving when it passes the tripper. On level track, if the trippers are located at a uniform distance in the rear of the block, this requirement is met by a single cam of the type described, in which the slope of the cam at each point corresponds to the maximum safe speed for the corresponding point on the track ;'that is, to the maximum speed from which the train can be brought to rest without entering the occupied block. The safe speed is a maximum at the time when the tripper is passed. It diminishes as the entrance to the occupied block is approached. Immediately in the rear of the occupied block it is zero. The corresponding position of the follower arm 13 is the bottom of its stroke when the contacts controlling the lamp 66 and the magnet valve 67 are opened irrespective of the speed of the train. The same cam will approximate the desired result on grades if the distance from the tripper to the entrance of the block is varied in accordance with the maximum distances necessary for stopping the train, with proper allowance for grade.

If it should be desirable to locate the trippers at a less distance from the entrance of the block than that which corresponds to the maximum travel of the cam 10, then instead of setting the cam back to the stop as shown in Fig. 1 it should be set back only through the angle which corresponds to the distance between the tripper and the entrance to the block. Fig. 3 shows one means of accomplishing this end.

The cam 28 instead of acting directly on the sector gear 22 acts on a crank 7 9, in opposition to a spring 80. The crank 79 carries a pawl 81 which engages notches 82- in a flange attached to the sector gear 22; but in its normal position the pawl 81 is lifted out of engagement with the notches by a foot 83 resting against the 'sideof the cas ing 1 as shown in dotted lines. Thus when the crank 79 is in its normal position the sector gear :22 is free to return; but each time the cam 23 is raised the sector gear 22 is set back one notch. By employing trippers having one, two, three or more raised portions, with depressions between them, the sector gear 22 and the cam 40 can be set back through different angles, corresponding to different distances in the rear of the entrance to the block.

lVhile I have disclosed and described certain practical embodiments of my invention it is apparent that modifications of the particular apparatus disclosed may be made without departing from the spirit of the in vention.

What I claim is 1. A controlling mechanism carried by a train and adapted to regulate its movement in accordance with one operating cycle or a selected part of said cycle, an actuating member therefor adapted to be displaced by trippers along the track, and means whereby the number of successive displacements of the actuating member determines the portion of the operating cycle selected for the controlling mechanism.

2. A controlling mechanism carried by a train and adapted to regulate its movement in accordance with one operating cycle or a selected part of said cycle, an actuating member therefor adapted to be displaced by trippers along the track, and means whereby the extent of displacement of the actuating member determines the portion of the operating cycle selected for the controlling mechanism,

3. In combination, a track divided into block sections, a train adapted to travel on said track, a controlling mechanism carried by said train, an actuating member therefor adapted to be displaced by contact with trippers along the track, means whereby a varying degree of control is ob tained in accordance with the number of trippers in a track section, trippers along the track in the path of the actuating member adapted to be displaced thereby during its passage without causing the actuating member to move, and locks adapted to prevent said displacement of the trippers.

4. A controlling mechanism carried by a train comprising a member whose move ment is proportional to the linear motion of the train, means for selectively setting said member in motion to accord with the distance of the train from a predetermined stopping point, a member whose motion is limited to a definite speed, and means for controlling the train dependent upon the relative motion of the first and second members.

5. A controlling mechanism carried by a train and adapted! to regulate its movement in accordance with one operating cycle or a selected part of said cycle, an

actuating member therefor adapted to be 1 displaced by trippers along the track, a pawl adapted to be operated by said actuating member, a ratchet controlled by said ELI J. BLAKE. 

